Ask GeoMan...
What is serpentinization? I'm a senior Chemical Engineering student at Clemson University and I can't seem to find a decent definition.
Serpentinization is a processes whereby rock (usually ultramafic) is changed, by the addition of water into the crystal structure of the minerals found within the rock. The most common example is the serpentinization of peridotite (or dunite) into serpentinite (the metamorphic equivalent). Here's where it gets a bit fuzzy:
Metamorphic processes usually involve the addition of heat and pressure: a rock is buried, heats up and is squeezed, and the minerals change in an attempt to regain equilibrium with the new environment (like shale to slate, or limestone
to marble). In the case of peridotite to serpentine, the process actually involves a reduction in heat and pressure. Peridotite starts out as a sub-crustal, upper mantle rock. If tectonic forces move it nearer to the surface, the reduction in T&P cause it to freak out, and the minerals (usually pyroxene and olivine) change to the mineral serpentine. No, I'm not mixing up rocks and minerals. Serpentinite is a rock which is composed of the mineral serpentine (which results in far too much confusion for most of us normal mortals).Click here for some additional information from my GeoTour to the serpentinites of the Josephine Ophiolite.
Hope this helps, and good luck with your studies. If you need any additional information, you know how to reach me.